The purpose of this RSDA proposal is to identify factors that might influence peripheral vascular reactivity in blacks. Research in health psychology has shown that many blacks exhibit a heightened peripheral vascular response to laboratory stressors (i.e., vascular hyper-reactivity) relative to their white counterparts. This vascular hyper-reactivity may contribute to the increased prevalence of hypertension among blacks. Based on a contextual model outlined in this proposal, a five year program of research is proposed for exploring the environmental, sociocultural, behavioral, psychological, and constitutional influences on vascular reactivity and other physiological processes that may play a role in the development of hypertension among blacks. Specifically, this research will examine the effects of an environmental variable, living in extreme poverty areas, on a number of biopsychosocial outcomes. The following hypotheses will be tested in black males and females: (1) Individuals living in census-defined high poverty areas will report higher perceived stress, lower social support, and exhibit increased sympathetic nervous system activity, augmented sodium retention, and greater vascular reactivity compared to individuals living in low poverty areas. (2) Residential environment will interact with constitutional, psychological and behavioral, and sociocultural factors to augment potentially pathogenic physiological activity. Thus, the following groups should the greatest physiological affects of living in a high poverty area: (a) older persons; (b) individuals low in anger expression and high in John Henryism and perceived stress and (c) persons low in perceived social support and religious participation. The proposed studies will be the first to examine the specific physiological pathways by which certain environmental, sociocultural, psychological, behavioral, and constitutional factors may be related to the development of hypertension in blacks.